In Ginsberg's "Howl," how would you characterize the world that Ginsberg describes? Is he being accurate or is he using hyperbole (exaggeration)?
How does he demonstrate the postmodern beliefs of combining fiction and nonfiction, multiculturalism, and the experimentation of new forms?
I'd say Ginsberg was describing the world as he saw it and to make his vision graphic and to convey the images as vivid as possible he did use hyperbole. His descriptions for the most part are realistic - based on actual occurrences. The reference to throwing potato salad at CCNY lecturers on Dadaismis about his friend Carl Solomon, who he met in a mental institution, and to whom the poem was dedicated. When the poem does describe surreal or seemingly hyperbolic images, this could be a reference to the hallucinogenic effect of drugs, (Ginsberg was in favor of recreational use) or those images were just exaggerated to give the poem more punch.
Figures of speech and metaphor have always been used in poetry. I understand that the question asked here is because Ginsberg is describing the problems in American society which have led to conformity, fear mongering and destroying the individuality of what he called the best minds of his generation - outcasts, namely. So, we want to know if his descriptions are accurate. Judging from the scholarship on the Beat Generation, the 50's and the following cultural revolution of the 1960s, I'd say that his descriptions were accurate, and their graphic nature is the power of the poem: a necessary exaggeration.
What sphinx of cement and aluminum bashed open their skulls and ate up their brains and imagination?
Is this literal or figurative? If it symbolizes conformity, then it is figurative but punches the point home with a graphic image. But it actually refers to a subway: symbolizing the death of his friend, Bill Cannastra. As far as the interpretation of the reader goes, it could mean both.
He does mix nonfiction with imagery - you might consider imagery to be fiction, but in poetry or in art, you're creating an "impression" of reality, so its status of nonfiction vs. fiction is not so relevant as the effect of its artistic depiction. Ginsberg embraces multiculturalism by demonstrating that the outcasts are part of America's diversity. The outcasts (homosexuals, mental patients, bums, drug addicts, communists, etc.) whom he says are being destroyed and whom he also calls "holy" and has hope for them yet. Formalistically, it does contain run-on sentences, a stream-of-consciousness style and later an incantation style, much like a prayer or refrain.
Given all the religious imagery/symbolism as well, this is a poem, that when it is not being blatantly literal, should be read as any myth or tale that is written for the purposes of communicating an idea. For some, Moloch is real; for others, Moloch represents oppression of capitalism and other institutions of the state.